Premier Campbell Newman says changes to the first home buyers grant will boost Queensland's building industry, as the Liberal National Party (LNP) Government prepares to hand down its first State Budget tomorrow.

The existing $7,000 first home buyers grant is being scrapped in October and being replaced with a $15,000 payment only available to those buying new homes.

Mr Newman has defended his decision to scrap the current first home buyers grant and the changes are needed to save the struggling construction sector.

"We've seen very high unemployment in that sector, the property industry in the doldrums," he said.

"It's necessary to put the money into the area which will do the most good and that's on the advice of all the information given to the Government.

"That's particularly about 'incentivising' people to invest in new property that's been constructed, to get people in the construction sector back to work.

"The property and construction industry has seen very high unemployment in recent years and this is a targeted initiative to get it going again."

However, the Real Estate Institute of Queensland (REIQ) has criticised the State Government's plan to overhaul the first home buyers grant.

"The first home buyers have actually been the oil of our real estate economy here in Queensland," he said.

"At the moment, in the less than $350,000 purchasing category, we know that the demand that's been fairly consistent in that area has been because of the first home buyers moving into that market."

But Queensland's largest residential property developer has welcomed an overhaul of the state's first home buyers scheme.

Kingsley Andrew, from Stockland, says new home sales are at the lowest level in years.

He says the extra stimulus is needed to create jobs in the building industry, because low interest rates alone have not worked.

"Low interest rates, combined with this incentive will have a profound impact and will act as a catalyst to get people back into jobs," he said.

"It's the jobs that creates the opportunity for Queensland, so the first home buyer buys that home, but most importantly it's the carpeneter that can then go and buy a home for themselves, whether that's a first home buyer or not."

Job cuts

Meanwhile, Police Minister and Member for Bundaberg, Jack Dempsey, says the State Government is trying to minimise public service job cuts.

More cuts are expected to be announced in tomorrow's Budget.

Mr Dempsey says ministers are trying to focus the cuts on head office roles.

"I can reassure the people of Queensland, the people of Bundaberg and other regional areas that that is the areas we'll be going at first," he said.

"Even right up to Budget day we are trying our best to look at other ways and other efficiencies to try to keep as many people in those positions."

Meanwhile, Opposition treasury spokesman Curtis Pitt says tomorrow's Budget will show if the Queensland Government is meeting its promise to reduce debt.

In last year's budget, state debt was forecast to reach $85 billion by 2014-15.

Mr Pitt says if the Government is sacking thousands of public servants, the savings should not be used to fund the LNP's election promises.

"What people should be looking for is that headline debt figure," he said.

"If that headline debt figure is anywhere near the figure previously put forward by the Treasury under Labor, this Government is basically sacking workers to pay for its election commitments."

Victoria's laws for disclosing political donations have long been criticised as among the weakest in the nation, but Premier Daniel Andrews says his proposed reforms will make the state's donations laws "the strictest donation laws in the country".